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Environmental
Job Vo.22172
Restoration
Contractor ERC Team u. c.. rw
Interoffice Memwandum a' 1 91C
TO D. A. St. John x.0-19 MTL Febmary 27,1999
nru:tc
See Below mc"' S. L. Winslow
RadCun Engineering
X.1-41/531-0700
suarecr: CVIAIF FSTIMATEFOR SWPING CONCRF•TF. CORE SAMPLES
.0 w
Sw.^Cnr !fib
The fulluwing calculations shoe that cure samples with a direct reading of equal to or less than
400,000 dpm/l00cm' will be bdow the definition ofralivactive mate rial as defined in 49 CFR 173.403
of 70 Bq/g (2F.3 pCi/g). Lachmmple will consistofcoacrete material from four, two inch co re
samples and enough water to mAe a slurry consi s:cary. The distribution of radionuclides is bused an
previous concrete samples wkm from the below grade Fuel Storage Basiu that would also be
representative of these concrete samples.
••von:
Cylinder Volume - nrh Radius of cam= core (r) = 1 inch
Concrete Density = 2.35 g/cm `Ileight of cure swrtple taken (h) — U.25 inches
27 pCi = Dq Maximum d irect reading on core = 400,000 dpm/IUUcat'
2.22 dpm = pCi
Calculations:
V — (3.14) (1 in.)'(0 25in) = 0-79 in' (16.4 cm `/irr) (4 cure samples) = 512 cm'
(400.000 dpm/5 L2 cm`) (cm'235 g) = 3.32E3 dpm/g
3.32L3 dpm/g (pCi/2.2 dpm) = 1.5 113 pCi/g or 55.4 E4'g
SLW:dld
Percent Distrtbation(%) Cong=ration (vCi/e )
"Co 0.17 235 pCi/g
17Cs 82 13F3 pCilg
WEu 0.33 4.95 pCi/g
"°Eu 0.05 7.5E-1 pCi/g
"ST 17 2.55E2 pCi/g
241
Ain
Z3912
'pu
0.005
0.1
7.5F.-2 pCi/g
1.5 -
Co ies:
S. 0.lvdarske X5-53
P. A. Newman X 3-41
RadCun Engineering File/LB X0-23
Document and into Serv ices 130.09
TUrAI-: 1.460, pCi/g
(-U00049